Jack for building material panels



Dec. 13, 196.0 E. J. FoTH JACK FOR BUILDING MATERIAL PANELS Filed Dec.15, 1957 2 sheets-sheet 1 FIE-1 Dec. 13, 1960 E. J. FoTH 2,964,293

' JACK FOR BUILDING MATERIAL PANELS Filed Deo. 13, i957 l 2 Sheets-Sheet2 United States Patent C) JACK FOR BUILDING MATERIAL PANELS Emery J.Foth, Elwood, Ill.

Filed Dec. 13, 1957, Ser. No. 702,569

1 Claim. (Cl. 254-4) This invention relates to a jack for elevatingbuilding material panels and more particularly to a jack useful inholding panels, such as plasterboard, against ceiling joists duringinstallation.

There have been several suggestions as to jack structures for raisingbuilding panels against ceiling joists but for several reasons none ofthem have been commercially successful. For several years, much homeconstruction has employed a so-called dry-wall instead of wet plaster.The dry-wall is made up of plasterboard panels ordinarily 4 wide andeither 8' or 12 in length. These panels of plasterboard have a cardboardcoating which should not be marred in the processes of nailing the boardto the wooden framework of the building, either wall partitions orceiling joists.

In order to permit one man to handle building material panels of thesize indicated, some mechanical contrivance is necessary to hold thepanel in place. In the absence of such mechanical help, the job ofplacing ceiling panels has required two or more workmen. It is believedthat among the reasons why a jack of the character to be described hasnot been commercially successful is the fact that a light-weight andeconomical structure has' never before been proposed. The jack of thepresent invention is both light-weight, easily operated and may beconstructed at a price well within the budget of those engaged inbuilding construction.

The primary object of this invention is to provide a new and improvedjack for raising building material panels.

Another object is to provide a jack of the character described having anovel and relatively inexpensive extensible supporting post.

Another object is to provide a jack of the character described made of aminimum number of parts of simple design and of particular light-weightconstruction.

A further object is to provide a jack for building material panelshaving a cable operated lift post requiring a minimum of maintenance.

Other objects, features and advantages of the present invention will beapparent from the following description of a preferred embodiment asillustrated in the accompanying drawings in which:

Figure l is an elevational View of a jack embodying the invention;

Figure 2 is an enlarged fragmentary sectional view through the cablewench and associated structure;

Figure 3 is a cross sectional view through the Wench taken substantiallyalong line 3 3 in Figure 2;

Figure 4 is a top plan view looking down upon the jack;

Figure 5 is a fragmentary enlarged sectional View taken along line 5 5in Figure 4;

Figure 6 is a fragmentary enlarged Sectional view taken along line 6-6in Figure l;

Figure 7 is a fragmentary enlarged sectional view adjacent the lower endof the supporting post; and

Figure 8 is a fragmentary enlarged sectional view taken along line 8--8in Figure 4.

`Patented Dec. 13,1960

ICC

The structure of the entire jack is best seen from Figures 1 and 4. Therough sub-flooring F is indicated as supporting the jack for purposes oflifting a building panel P mounted upon a framework generally indicated9.v The building panel may be a 4' X 8 sheet of plasterboard intended tobe nailed to ceiling joists in a residential type building. The jack tobe described in detail is intended to elevate the building panel againstthe joist and hold it in that position while the workman nails it at itsedge and along each of the joists against which it is held.

The jack has an upright extensible post generally indicated 10 includingan outer post 11 and an inner post 12. Each of the posts is made oftubular metal stock of lightweight but fairly stiff material. It hasbeen found that electrical conduit is particularly useful and has thequalities desired. The outer post 11 is considerably larger than theinner post as illustrated. The inner post may freely move or telescopewithin the outer post. Y

The posts are held in an upright position over the floor F by four (4)foldable legs 13 each pivoted to a bracket 14 more particularlyillustrated in Figure 6. The bracket is slidable upon the outer post 11and held in position by a spring pressed detent 15 engageable inappropriate stamped openings in the outer post. Chains 16 prevent thelegs from swinging outwardly more than as illustrated in Figure 1, thechains being attached to the lower end of the outer post and to eachleg. The legs may be folded by retracting the spring pressed member 15,raising the collar 14 upon the post so that the detent may engage in anopening 17 in the outer tube, placing the legs in the dotted lineposition in Figure l. In this position the casters 18 will rest in aposition above the lower end of the outer post.

As mentioned above, the building panel is supported upon a frame 9 sothat it may be forced upwardly against ceiling joists. This frame has anelongated leaf spring 20 removably attached to a central block 21 by afastener 22 so that the block may be inserted into the inner post 12,and held therein by sheet metal screws 23. Cross bars 34 are removablyattached to the outer ends of the leaf spring in the manner indicated inFigure 5. Each cross bar 24 may be about 3' long and equipped with abracket 25 at its center having a threaded shank 26 to pass through anopening in the end of the spring and be held thereon by a wing nut 27.The frame is thus cornposed primarily `of the spaced and generallyparallel bars 24 so that the panel may rest upon these bars asillustrated in Figure l, The leaf springs supporting the bars and thusthe panel, give the assembly some resiliency to take up anyirregularities because of an uneven lloor on which the jack sets or anyunevenness in the ceiling joists. The leaf spring also permits the panelto be tightly held against the joist with the pressure exerted by thebowed spring.

One of the structural parts of the present jack which contributes to itslow cost is the elevating structure employed between the inner and outerposts. These posts are extended in the present invention by the use of acable lift. It is preferred that the inner post be considerably smallerthan the outer and for example, might be 11/2 in outer diameter whereasthe outer post might be 297/16" in outer diameter. A cap 30 is made oflight-Weight aluminum and fastened to the upper end of the outer post toguide the inner post. For guiding purposes, the cap is provided with anoff-center opening 31 which will place the inner post adjacent one sideof the outer post.

A further guide of the inner post is provided by the mechanism of thecable lift. The housing 32 is a casingv provided to slip over the outerpost and be fastened thereto as by fasteners 33. The housing isdownwardly open and receives therein a drum 34 upon which a cable 35 iswound in such a manner that one end portion 36 ex-` tends into the outerpost through an opening 37 provided for this purpose. The end 36 of thecable is fastened Yto the lower end of the inner post 12 by passing anenlargement 38 thereon past a slot 39 in the lower end of the innerpost. The cable wound upon the drum also bears against the inner post 12as illustrated in Figures 2 and 3, and thus provides a guiding bearingspaced from the cap 30 and serving to keep the inner post against oneside of the outer post. In this manner, a space is left within the outerpost extending along side the inner post through which the cable 36 mayfreely pass.

The drum is mounted upon a shaft 40 to which an operating handle 41 isexternally attached. Preferably, the drum is made up of two parts, a cupshaped part 42 having teeth 43 about its base, and a cap part 44 closingthe cup shaped part. The cable may be conveniently fastened to the drumby passing an enlargement 45 past a slot formed between the cooperatingparts of the drum. A manually operated dog 46 is pivotally secured tothe housing in position to engage the teeth on the drum holding the drumfrom unwinding the cable.

The above description of the elevating mechanism Will indicate that aminimum number of parts are so arranged that maintenance of the unit ispractically nil. The housing, the drum, the cap and the collar formounting the legs may all be of light-weight metal casings. The innerand outer posts are preferably electrical conduit type tubular membersand the construction is such that the cable lift may, most convenientlyand easily, be operated and maintained. In operation, one man may toss abuilding panel up onto the upper frame and then elevate the same againstthe ceiling joists. Operation of the locking dog 46 will hold the jackextended while the same workman nails the panel in place.

The foregoing detailed description has been given for clearness ofunderstanding only and no unnecessary limitations should be understoodtherefrom for some modications will be obvious to those skilled in theart.

I claim:

A jack for elevating building material panels, comprising: a wheeledbase with an upright extendable and adjustable support secured to thebase, said support having a pair of round tubular posts ,gf dissimilarsize, one within the other and said one being extendable lengthwise ofthe other and adjustable angularly with respect to the other post; a capmember teles'coped over the upper end of the larger post and having anoff center opening therein aligned with the interior of the larger postfor guiding the smaller post in an upright path within the larger postgenerally closely adacent one side and spaced from the opposite side ofthe larger post, said cap opening permitting the smaller post to turnwithin the larger post; a cable drum mounted on the exterior of thelarger post spaced at a distance below the upper end thereof and at agreater distance above said base, said cable drum having one sideprojecting into said larger post on said opposite side thereof; a cableon said drum having one end attached to the lower end of the smallerpost and its other end attached to the drum so that an intermediateportion of said cable extends generally parallel to and against thesmaller post for elevating the smaller post when the cable is wound uponsaid drum, said cap and said cable on said drum engaging the smallerpost at longitudinally spaced points to maintain the posts inpredetermined alignment during extension and retraction thereof; and aframe upon the upper end of the smaller post for receiving a panel to beelevated, said smaller post being adustable in height and angularposition relative to said base to position a building panel as desired.

References Cited in the ile of this patent UNITED STATES PATENTS 818,228Butler Apr. 17, 1906 2,378,984 Couture June 26, 1945 2,604,303 GradyJuly 22, 1952 2,655,412 Jones Oct. 13, 1953 2,672,319 Nelson Mar. 16,1954 2,765,201 Phillips Oct. 2, 1956 2,794,612 Clifton June 4, 1957

